"This is a moment for us to define ourselves. Are we willing to ... take a stand. No terror and murder in our names," Abdullah tweeted.

Kashmir, divided between India and Pakistan since 1947, is one of the most heavily militarised spots on earth with a long history of conflict.

The mountainous region is home to dozens of armed groups fighting for independence or a merger of the territory with Pakistan.

Mirwaiz Umar Farooq, head of All Parties Hurriyat (Freedom) Conference, a political coalition opposed to the Indian rule of Kashmir, also condemned the attack.

"As the unfortunate news of the Yatris killing reaches us leadership and people of Kashmir are deeply disturbed and saddened and strongly condemn it," Farooq said on Twitter.

Jammu and Kashmir, India's only Muslim-majority state, has since 2014 been governed by the pro-India People's Democratic Party in an unpopular coalition with Modi's ruling Hindu nationalist Bharatiya Janata Party (BJP).

Analysts say this has intensified public opposition to Indian rule in Kashmir.

Tensions have also been high around the first anniversary of the death of charismatic rebel leader Burhan Wani, who was shot dead by security forces on July 8 2016.

The death of the 23-year-old, who had built up a big following on social media, sparked a huge outpouring of grief in Kashmir.